Yeah throw a bit more air at it! Around 25psi with a dawes to eliminate spikes.
You'll need a voltage clamp on the map to fool ecu... Get yourself an egt gauge and boost gauge first.
All that won't really do much for intake temperatures other than make them hotter.
Egts will definitely be cooler but I doubt if it'll make difference to coolant temps. If you're getting max 112 degree, that ain't too bad considering that you're towing.
Mine see 110-115 quite frequently when towing. Just last month I was towing a mates 3t dual axle Jayco through the hills on a 35degree day, I pushed as hard as I could trying to boil it.. Managed to see intake temps as high as 126 degrees and coolant temps of 117 degrees... Unfortunately my clutch started slipping badly so I couldn't keep up it.
If were me I'd be changing your coolant back to the original 30% mix pre service campaign, gets rid of heat better than the 50% mix, also go back to the lower pressure radiator cap.
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